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Cardiomiopatia peripartum
171
Reviews in Health Care 2011; 2(3): 171-184
Corresponding author
Francesco Giallauria, MD, PhD
Cardiac Rehabilitation Unit
Università di Napoli “Federico II”
Via Pansini 5
80131 Napoli (Italy)
Email: giallauria@libero.it
Exercise stress testing
in clinical practice
Il test da sforzo nella pratica clinica
Te c h n i q u e s
Francesco Giallauria 1, Alessandra Grieco 1, Angelo Russo 1, Luigi Maresca 1, Maria Mancini 1,
Alessandra Vitelli 1, Sara Aurino 2, Carlo Vigorito 1
1 Department of Clinical Medicine, Cardiovascular and Immunological Sciences, Cardiac Rehabilitation Unit,
Università di Napoli “Federico II”, Napoli (Italy)
2 Department of Preventive Medicine, Università di Napoli “Federico II”, Napoli (Italy)
Abstract
Exercise stress testing is an important diagnostic tool for evaluating patient’s cardiovascular perfor-
mance. e present review describes the accuracy and the value of exercise stress testing in different
settings: aer an acute coronary event, aer percutaneous coronary intervention or coronary arte-
ry bypass gra; in patients risk assessment before non-cardiac surgery; in diabetic population; in
patients with baseline electrocardiographic abnormalities. Moreover, this review provides insights
relating to test accuracy in women and geriatric patients. Finally, this review explores new varia-
bles/parameters (dyspnea, chronotropic incompentence, heart rate recovery, functional capacity,
integrated scores) that in the last few years added an incremental value to conventional analysis of
exercise-induced angina or electrocardiographic changes.
Keywords
Exercise stress testing; Acute coronary event; Percutaneous coronary intervention; Coronary artery
bypass gra; Dyspnea; Chronotropic incompentence; Heart rate recovery; Functional capacity; Women;
Elderly
Disclosure
The authors declare that they have
no nancial competing interests
Narrative
review
172 Reviews in Health Care 2011; 2(3) © SEEd Tutti i diritti riservati
Exercise stress testing in clinical practice
F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
Exercise stress testing after acute coronary event
e current American College of Cardiology (ACC) and American Heart Association (AHA) guide-
lines recommend submaximal or low-level ExT as early as 3-5 days aer an uncomplicated coronary
event prior to discharge unless the patient has undergone percutaneous coronary intervention (PCI) or
coronary artery bypass gra (CABG) surgery and been fully revascularised [1].
Maximal symptom-limited ExT can be performed 30 days aer the coronary event. e submaximal
exercise test is stopped when one of the following endpoints occurs:
peak heart rate of 120 to 130 beats per minute or 70% of the maximal predicted heart rate for age;
•
peak work level of 5 metabolic equivalents (METs);
•
mild angina or dyspnea;
•
exercise-induced ST-segment depression of 2 mm or more;
•
exertional hypotension; or
•
hree or more consecutive ventricular premature contractions.
•
Usually, if a patient is able to complete a stress test at an acceptable cardiovascular workload (5 or more
METs) without any ECG changes, angina, hypotension, significant ST-segment depression or frequent
ventricular premature contractions, he/she is deemed low-risk for a recurrent cardiac event during the
next year [2].
Karlson et al showed that among patients hospitalised with a suspected or confirmed acute ischemic
event but either no or only minor myocardial necrosis, the maximum working capacity at a symptom-
limited ExT was independently associated with the long-term prognosis but not with other signs of myo-
cardial ischemia [3]. Moreover, further predictors for long-term prognosis were age, a history of acute
myocardial infarction, current smoking, and diabetes mellitus. Interestingly, mechanical revascularisa-
tion during the subsequent 5 years interacted with the influence of symptoms of angina during test and
prognosis.
If the patient presents resting ECG abnormalities which preclude interpretation of exercise-induced
ischemia, the addition of nuclear imaging as well as echocardiography is suggested. However, there is a
general agreement that performing a symptom-limited ExT aer an acute myocardial infarction (MI)
using the Bruce protocol 3 days aer admission determines a very low incidence of complications [4-
6]. A meta-analysis showed that if the pre-discharge ExT is normal following an acute MI, there is a <
10% event rate at 1 year; if abnormal, the event rate increased to 10-20% [7]. Postinfarction functional
capacity is also crucial: the ability to achieve an adequate cardiac workload (pressure rate product hi-
gher than 21,700) has been associated with an efficient myocardial blood supply and with a favorable
6-month prognosis [8].
Exercise stress testing after percutaneous
coronary intervention
In patients who have undergone recent Percutaneous Coronary Intervention (PCI), recurrence of
symptoms itself has low sensitivity and specificity for detecting restenosis and myocardial ischemia.
ExT may provide useful information on symptoms and functional capacity of the patient; however, a
meta-analysis showed that ExT alone has a poor sensitivity (46%) and a moderate specificity (77%) for
the identification of post-PCI restenosis [9].
e use of nuclear imaging increases the sensitivity to 83% without affecting specificity [10]. In addi-
tion, ExT with imaging adds incremental information (ejection fraction and wall motion) and is useful
to localise the region of ischemia as well as assists the interventionalist in identifying the culprit lesion
[11-13]. Of note, symptom-limited ExT the day aer stent implantation is safe [14].
Exercise stress testing in clinical practice
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F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
In the first month post-PCI, an abnormal ExT may indicate inadequate intervention or revasculariza-
tion result, or a successful result with impaired coronary flow reserve in the site [15].
erefore, for routine follow-up in asymptomatic patients, it has been suggested to perform an ExT
with imaging 2-3 months aer PCI in order to avoid false positive results. At that epoch, ExT is useful
to diagnose restenosis or new stenosis in asymptomatic patients as well as document functional capa-
city and aid in early identification of patients at risk for subsequent events [16].
Exercise stress testing after coronary artery bypass graft
In order to allow sternal healing and appropriate early rehabilitation, there is a general agreement on
waiting 2-3 months aer surgery before doing a symptom-limited ExT. In post-coronary artery bypass
gra (post-CABG) patients with an abnormal baseline ECG which are non-diagnostic for ischemia,
an imaging modality should be added. Exercise-induced ischemic ST-segment depression may persist
when incomplete revascularisation is achieved, as well as in 5% of patients who have had complete
revascularisation [17,18]. e sensitivity as well as the prognostic value of the test is greater in the late
period (5-10 years aer CABG) than in the early period (first year aer CABG) [19,20].
Exercise stress testing in risk assessment
before non-cardiac surgery
ExT is useful to identify coronary artery disease (CAD) in asymptomatic patients, especially in those
who do not exercise regularly, or to stratify cardiovascular risk in patients with known CAD prior
to non-cardiac surgery. Findings which increase risk of perioperative cardiac events include marked
exercise-induced ST-segment depression or exercise-induced angina at low workloads, poor exercise
capacity (< 5 METs), an abnormally low peak systolic blood pressure (< 130 mmHg), or a fall in systolic
blood pressure during exercise > 10 mmHg below standing rest values [21,22].
According to 2007 ACC/AHA guidelines, continued emphasis should be given to preoperative clinical
risk stratification, with noninvasive testing reserved for those patients in whom a substantial change in
medical management would be anticipated based on results of testing [23]. Moreover, the implemen-
tation of the ACC/AHA guidelines for cardiac risk assessment prior to non-cardiac surgery in a con-
sultant anaesthesiologist-led preoperative clinic reduced preoperative resources utilization, improved
medical treatment and preserved a low rate of perioperative cardiac complications [24].
Notably, in clinical practice, ExT have a poor positive predictive value for identifying which patients
will have a perioperative cardiac event, suggesting that perioperative MI’s may not share the same
pathophysiology as non-operative MI’s [25,26]. In addition, patients with functional limitations
such as arthritis or other medical problem will likely require an alternative form of stress test such
as a pharmacological nuclear or echocardiographic stress test. To reduce the risk of these complica-
tions, some Authors have reported on the utility of intraoperative transesophageal echocardiogra-
phy as a complementary monitoring tool in non-cardiac surgery. However, although this approach
is now well established in patients undergoing cardiac surgery, there are no guidelines for intrao-
perative transesophageal echocardiography application in non-cardiac surgery, and little literature
exists on patient outcome, logistics, financial impact, medico-legal implications and safety [27].
Finally, taking into consideration the higher risk of coronary angiography and revascularisation in
high-risk patients, the current approach is moving away from extensive noninvasive preoperative
risk stratification towards selective noninvasive testing and aggressive pharmacological peri-opera-
tive therapy [28].
174 Reviews in Health Care 2011; 2(3) © SEEd Tutti i diritti riservati
Exercise stress testing in clinical practice
F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
Exercise stress testing in diabetic patients
Coronary artery disease is the leading cause of morbidity and mortality in patients with diabetes mel-
litus [29]. In fact, patients with diabetes have the same risk of myocardial infarction as do non-diabetic
subjects with a history of infarction. For this reason, diabetes should be considered as a CAD equiva-
lent [30].
Current diagnostic tools include ExT, stress echocardiography, stress myocardial perfusion imaging,
and cardiac catheterisation [31]. Although cardiac catheterisation is useful, it is generally reserved
for patients in whom invasive intervention is suitable. e American Diabetes Association (ADA)
recommends ExT alone in symptomatic patients with 2 or more CAD risk factors or an abnormal
resting ECG. Stress echocardiography is a useful, noninvasive procedure; however, there is limited
experience with this technology in the diabetic population. Recently accumulated data support both
diagnostic and prognostic roles for stress myocardial perfusion imaging, particularly with ECG-gated
single-photon emission computed tomographic imaging. In symptomatic patients with diabetes, the
presence and extent of abnormal stress myocardial perfusion imaging findings have been found to
be highly accurate independent predictors of subsequent cardiac events: 18% to 26% of asympto-
matic patients with diabetes have perfusion defects consistent with CAD. However, cardiovascular
risk factors are not predictive of abnormal stress myocardial perfusion imaging findings even though
duration of diabetes and abnormal ECGs are. A recent study showed that in diabetic asymptomatic
patients, combining a myocardial scintigraphy with a maximal ECG stress test is effective in detecting
more patients with coronary stenoses and predicting cardiovascular events [32]. However, ExT has a
good negative predictive value for cardiac events (97%), is cheaper, and should therefore be proposed
first [32].
Finally, related issues specific to diabetic patients undergoing ExT include:
similar diagnostic sensitivity and specificity of ExT for identification of CAD in patients presenting
•
with angina;
lower diagnostic accuracy in asymptomatic diabetics, who may not manifest angina;
•
reduced functional capacity, associated with increased cardiac morbidity and mortality;
•
abnormal HRR.
•
Exercise stress testing in geriatric patients
e ever-increasing number of older patients requiring diagnostic and prognostic assessment for
CAD has necessitated accurate, noninvasive techniques applicable to this age group [33]. Exercise
electrocardiography is more challenging in the elderly. Elderly subjects are more likely to have baseli-
ne ECG abnormality rendering the ECG non-diagnostic [34]; and less likely to achieve adequate and
diagnostic exercise workload due to arthritis, musculoskeletal disease, peripheral arterial disease,
and reduced cardiopulmonary reserve [35]. Of note, in old population with higher prevalence of
CAD, a borderline exercise test is much more likely to indicate real disease than in a low-risk younger
population. In elderly patients able to exercise, workload achieved is independently predictive of
cardiac morbidity and mortality [36,37]. Although the performance of exercise stress testing may
pose several problems in older patients, it is not contraindicated [38]. Recently, McAuley et al [39],
using ExT in healthy elderly men, observed independent and joint inverse relations of body mass
index and cardiorespiratory fitness to mortality, suggesting fitness and fatness as mortality predictors
in these subjects. For those patients with a non-diagnostic ECG or not able to exercise or achieve an
adequate workload, adjunctive imaging may determine the extent and severity of ischemia with more
accuracy [33,34].
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F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
Patients with left ventricular hypertrophy
on their baseline ECG
ExT has been demonstrated to be sensitive (68% vs. 72%) but not so specific (69% vs. 77%) for detec-
ting CAD [40]. Most testing labs will require ≥ 2 mm of ST-segment depression in the presence of le
ventricular hypertrophy by Sokolow-Lyon (voltage) criteria to report a significant ST-segment change
[40]. e major reason behind the false positive ST-segment changes is the mild subendocardial ische-
mia secondary to concentric hypertrophy and microvessels, in the setting of relatively normal epicar-
dial coronary arteries.
Patients with a right bundle branch
block on their baseline ECG
Patients with right bundle branch block (RBBB) typically manifest wide QRS complexes and T wave in-
version in precordial leads V1-V3 on their baseline ECG, so exercise-induced ST segment depression is
non-diagnostic if it occurs in leads V1-V3 [40]. However, in the remaining leads, ST-segment changes
are diagnostic for ischemia, with the resulting sensitivity and specificity being similar to a patient with
a normal baseline ECG. erefore, it is still considered appropriate to perform ExT without imaging as
an initial test in patients with RBBB.
Exercise stress testing in women
In women, sensitivity (61%) and specificity (69%) of ExT for detecting CAD using ST-segment changes
or exertional angina are significantly less than for men [41]. However, low exercise capacity, abnormal
HRR, inability to achieve target heart rate, and integrative scores were independently associated with
increased cardiovascular and total mortality. Several reasons for the lower test accuracy in women
should be considered. Women have a lower exercise capacity and achieve target heart rate less oen
than age-matched men [41]. Furthermore, women present with manifestations of CAD at an older age
than men and thus unable to achieve as great a workload [42]. Women more oen have resting ST-T
changes and lower ECG voltage [41]. Finally, sex hormones (estrogen) can affect ST-segment changes
and have a digoxin-like effect. Premenopausal women are more likely to have false positive ExT than
postmenopausal women, and false positive tests occur more frequently when estrogen levels are high
[43]. Postmenopausal women on hormone replacement therapy with estrogens showed an increase in
false positive ischemic ST-segment depressions on ExT [44]. Women also present smaller coronary
vessel size which may reduce the maximal flow heterogeneity and potentially decrease the amount of
ST-segment changes. Finally, during the exercise portion of the ExT, women with moderate sized bre-
asts may get excessive ECG motion artifact from the breasts pushing and pulling on adjacent skin and
precordial ECG leads making it difficult to interpret ST-segment changes.
Exercise stress testing in women with
polycystic ovary syndrome
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in premenopausal wo-
men, with 6-7% prevalence worldwide, mainly characterised by chronic ovulatory dysfunction, insulin
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F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
resistance and hyperandrogenism [45]. Metabolic-hormonal features observed in PCOS represent an
intriguing biological model illustrating the relationship between hormonal pattern and cardiovascular
risk profile [46]. PCOS women, even at an early age, have a clustering of cardiovascular features, such
as obesity, low-grade inflammation and metabolic syndrome [46,47].
ExT represents a useful tool at evaluating cardiopulmonary functional capacity and autonomic fun-
ction in PCOS women [48-50]. Further studies are strongly encouraged in order to investigate the
prognostic value of ExT in this group of patients.
Endpoints and post-exercise recovery
Criteria for the achievement of appropriate workload during ExT are reported in the box.
e test’s capacity for detecting significant CAD is reduced whether a patient is unable to reach any of
these endpoints for whatever reason [40]. Certain occurrences during the test strongly suggest an im-
mediate stop of the ExT and have the patient sit down and recover. ese include development of signi-
ficant angina > 10 mmHg fall in systolic blood
pressure, central nervous symptoms, signs of
decreased perfusion, ischemic ST-segment ele-
vation ≥ 1.0 mm in leads without Q waves
(other than V1 and aVR), ischemic ST-segment
depression ≥ 3.0 mm, equipment problems, re-
quest by patient to stop, or significant arrhyth-
mia. Adverse findings during ExT which indi-
cate future cardiac morbidity and mortality are
shown in the box.
To note, the recovery stage is the only time
where abnormalities manifest. Recovery conti-
nues until the patient’s heart rate, systolic blood
pressure, and ECG have returned to near baseli-
ne levels (usually within 9 min). In addition, be-
cause the patient is resting in recovery, the ECG
has a good baseline with minimal motion arti-
fact. During recovery, patients can have major
ischemic ECG changes even when the exercise
Goals that the patient should achieve to
obtain an adequate workload during ExT
85% of their maximal age-predicted he-•
art rate, i.e. 0.85 × (220 − age of patient
in years). This results in an increase in co-
ronary blood ow of 2-4 fold in non-ste-
nosed coronary arteries
A pressure-rate product or double product •
of > 20,000, chosen because a pressure-
rate product > 20,000 results in an incre-
ase in coronary blood ow of 2-3 fold in
non-stenosed coronary arteries
An ischemic endpoint (i.e. reproduced pa-•
tient’s usual angina so that they wish to
stop or signicant ischemic ST segment
changes). Exercise-induced ischemic
ECG changes occur more frequently, and
usually precede onset of angina
Events that portend a poor prognosis during ExT
Poor exercise capacity (< 5 METs)•
Abnormally low peak systolic blood pressure (< 130 mmHg) or a fall in systolic blood pressure •
during exercise of 10 mmHg or more below standing rest values
Exercise-induced angina, especially at low workloads•
≥• 2 mm of ischemic ST-segment depression at a low workload (≤ Bruce stage 2 or heart rate ≤
120 beats per minute)
Early onset (Bruce stage 1) or prolonged duration (> 5 min) ST-segment depression•
Multiple leads (5 or more) with ST-segment depression•
Exercise-induced ST-segment elevation (excluding aVR or leads with Q waves)•
Ventricular couplets, triplets, sustained (> 30 s) or symptomatic ventricular tachycardia•
Abnormal HRR•
Exercise stress testing in clinical practice
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F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
portion appeared normal. Also, tachy-arrhythmias including ventricular tachycardia and paroxysmal
atrial fibrillation, or brady-arrhythmias such as second or third degree heart block, can occur.
ST-segment depression and ventricular ectopy in the recovery phase
e optimum ECG is more likely to be acquired early in recovery. Changes in recovery are just as signi-
ficant for predicting risk for cardiac events (angina, MI, cardiac death) as those that occur during exer-
cise [51]. Several studies showed that exercise-induced ventricular arrhythmias (defined as premature
ventricular contractions > 10% of all ventricular depolarisation during any 30-s recording, or a run of
three or more premature ventricular contractions during exercise or recovery) independently predict
increased mortality [52]. One study of 29,244 men and women (mean age = 56 years; 70% men) who
had been referred for ExT (with no history of heart failure, valve disease, or arrhythmia) found that
frequent ventricular ectopy (> 7 premature ventricular contractions/min, bigeminy, trigeminy, cou-
plets, triplets, ventricular tachycardia, flutter, torsade, or fibrillation) during recovery but not during
exercise was an independent predictor of increased morbidity and mortality [53]. Despite these studies,
it remains unclear whether exercise-induced frequent ventricular ectopy is an independent predictor
or a marker of underlying heart disease.
Heart rate increase at the onset of exercise stress testing
e initial response of heart rate to dynamic exercise has been proposed as having prognostic value in
limited studies that have used modalities other than the treadmill.
In a study population of 1,959 patients referred for clinical ExT, Leeper et al [54] reported that decrea-
sed heart rate changes at all initial relative exercise workloads were associated with significantly incre-
ased all-cause mortality. Interestingly, the heart rate rise at one-third total exercise capacity, however,
was the only early heart rate variable that significantly predicted both all-cause and cardiovascular risk
aer adjustment for confounders. e Duke Treadmill score, however, was superior to all heart rate
measurements in the prediction of cardiovascular mortality.
Heart rate recovery (HRR)
During recovery, vagal reactivation results in increased parasympathetic tone and a decline in heart
rate. is decline is blunted with decreased myocardial function and reduced exercise capacity. Mul-
tiple investigators have confirmed that abnormal HRR, defined as failure of heart rate to decrease 12
beats or more during the first minute aer peak exercise (while the patient remains standing) indepen-
dently predicts an increased mortality in men and women [55,56]. Further, the greater the fall in heart
rate in the first minute of recovery, the lower the subsequent mortality. An abnormal HRR likely reflects
decreased vagal reactivation, and has been directly related to abnormal heart rate variability and insu-
lin resistance [49,57,58]. Patients with a HRR of less than 25 beats per minute likely have autonomic
imbalance; in one cohort of middle-aged men, this independently predicted sudden death [59].
It should be noted that both chronotropic incompetence and HRR predict cardiovascular mortality in
patients referred for exercise testing for clinical reasons [60].
Myers et al [60] reported that chronotropic incompetence was a stronger predictor of cardiovascular
mortality than heart rate recovery, but risk was most powerfully stratified by these two responses toge-
ther. ese Authors suggested that the simple application of heart rate provides powerful risk stratifica-
tion for cardiovascular mortality from the ExT, and should be routinely included in the test report [60].
Systolic blood pressure recovery
e systolic blood pressure should fall rapidly aer cessation of exercise by more than 15% at 3 min
aer stopping; myocardial ischemia may delay this decline [61]. Abnormal systolic blood pressure
178 Reviews in Health Care 2011; 2(3) © SEEd Tutti i diritti riservati
Exercise stress testing in clinical practice
F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
recovery is significantly associated with severe CAD [62]. Laukkanen et al [61] reported that a systolic
blood pressure > 195 mmHg aer exercise or a rise in systolic blood pressure of more than 10 mmHg/
min for 2 min aer exercise was associated with risk of future MI.
Exercise-induced bundle branch blocks and supraventricular arrhythmias
Exercise-induced transient le bundle branch block occurs in about 0.4% of patients, renders the le
bundle branch block (LBBB) portion of the ECG uninterpretable for ischemia, and in one series inde-
pendently predicted a higher rate of death and major cardiac events [63]. However, if ischemic ST-seg-
ment changes occur before or aer the le bundle branch block has resolved, the ExT is still sensitive
for CAD. If a transient LBBB develops at lower heart rates ≤ 120 beats per minute or with classic angina,
this may correlate with significant CAD (oen proximal stenosis of the le anterior descending artery)
[64]. In contrast, if the LBBB develops at rates > 120 beats per minute it is more likely a rate-related
phenomenon, and several studies have confirmed this to be associated with normal coronary arteries
[64]. Exercise-induced transient RBBB is less common, occurring in about 0.1% of patients; a single
study noted this was associated with CAD [64].
Supraventricular arrhythmias (atrial premature beats, atrial fibrillation, atrial flutter, supraventricular
tachycardia) are commonly induced by exercise and seen in up to 10% of normals and in up to 25%
of those with known or suspected CAD; they appear to be more common in patients with underlying
heart disease. However, they are not diagnostic for CAD, nor do they predict adverse long-term car-
diovascular outcomes [65].
Scores, functional capacity, and new developments
Integrated treadmill scores
Among the various scores that can be calculated based on traditional results as well as on other functio-
nal and hemodynamic aspects of the ExT that have prognostic value, the Duke Treadmill Score (DTS)
is the most commonly used [66,67]. e DTS is easily calculated as follows:
DTS = Exercise time − (5 × ST deviation) − (4 × Angina index)
Where:
Exercise time is calculated in minutes;
•
ST deviation is the maximal exercise-induced ST-segment deviation in millimeters;
•
Angina index is the exercise angina with 0 = none, 1 = non-limiting, 2 = exercise limiting angina.
•
e DTS is then classified into risk as follows: low risk ≥ 5, moderate risk -10 to +4, and high risk ≤ -11
[66,67]. Studies adopting the DTS score reported that CAD is more prevalent in men of all risk groups;
however, amount and severity of disease increased from low risk to high risk in both genders as well as
a higher mortality by all risk groups in men than women [66,67].
Functional capacity and metabolic equivalents
e metabolic equivalent is a unit of resting oxygen uptake which measures energy expenditure; 1
MET equals 3.5 ml oxygen uptake/kg/min. In studies of men and women referred for exercise testing,
determination of exercise capacity in METs is a more powerful predictor of mortality than other esta-
blished risk factors for cardiovascular disease [56,68]. Peripheral vascular endothelial function corre-
lates with exercise capacity in both genders, even in the absence of CAD. Impaired functional capacity
Exercise stress testing in clinical practice
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F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
and abnormal HRR appear to be strongly and independently associated with lower socio-economic
status [69,70]. Usually, major or sudden reductions in a patient’s functional capacity (or MET level)
should suggest further evaluation.
ExT in cardiac rehabilitation programs and exercise prescription
Cardiac rehabilitation in patients with CAD results in a substantial reduction in mortality and mor-
bidity [71-73]. A typical outpatient cardiac rehabilitation program consists of weekly exercise for 12
weeks, allowing the development of an individualised exercise prescription that is safe and effective.
e program should not improve the patients exercise capacity, but will also bolster confidence and
psychological well-being, allow counseling on risk factor modification, and also establish a long-term
exercise maintenance program [71-73]. According to AHA Guidelines, ExT should be used to risk
stratify patients prior to starting any exercise program [74-81].
Conclusions
Implementing traditional variables with new parameters is diagnostically and prognostically important
in patients undergoing ExT. ExT has an improved accuracy and is more clinically relevant when mul-
tiple risk parameters (ST-segment deviation,
chest pain, exercise time, chronotropic compe-
tence, heart rate recovery, blood pressure reco-
very, ventricular arrhythmias) are incorporated
into the final test result evaluation. ese varia-
bles and related integrative scores, are important
markers of current cardiovascular functional
status, and also predict future morbidity and
mortality. Novel variables and scores could help
stratify risk, and so should be an integral part of
the ExT report.
Questions for further research:
Implementing traditional variables with new
parameters is diagnostically and prognosti-
cally important in patients undergoing ExT.
Novel variables and scores could help stra-
tify cardiovascular risk especially in women
and geriatric patients; and so should be an
integral part of the ExT report.
The review in brief
Clinical question This review aims at analysing the usefulness of exercise stress testing (ExT) as a diagnostic tool
for evaluating patient’s cardiovascular performance in different settings.
Type of review Narrative
Search of the literature PubMed, with keywords: exercise stress testing, acute coronary event, percutaneous coronary
intervention, coronary artery bypass graft, dyspnea, chronotropic incompentence, heart rate
recovery, functional capacity, women, elderly
Conclusions We found that ExT has an improved accuracy and is more clinically relevant when multiple risk
parameters (ST-segment deviation, chest pain, exercise time, chronotropic competence, heart
rate recovery, blood pressure recovery, ventricular arrhythmias) are incorporated into the nal
test result evaluation. The present review dealt with new variables/parameters that in the last
few years added an incremental value to conventional analysis of exercise-induced angina or
electrocardiographic changes
Limitations Search limited to the studies published in English
180 Reviews in Health Care 2011; 2(3) © SEEd Tutti i diritti riservati
Exercise stress testing in clinical practice
F. Giallauria, A. Grieco, A. Russo, L. Maresca, M. Mancini, A. Vitelli, S. Aurino, C. Vigorito
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